Dental instrument



Nov. 10, 1936. G. COBLE DENTAL INSTRUMENT Filed April 6, 1936 Saws/14M Lac Ian, G. ob l6,

Patented Nov. 10, 1936 UNITED STATES PATENT OFFICE DENTAL INSTRUMENT Lucian G. Coble, Greensboro, N. 0.

Application April 6, 1936, Serial No. 73,028

Claims.

This invention relates to a novel dental instrument and particularly to an implement for facilitating the proper positioning of teeth in a denture relatively to the lip line of a patient.

In the preparation of a denture for a patient it is, of course, essential that the teeth, and particu larly the frontal teeth, be properly located or positioned in the denture with respect to the lips or lip line of the patient. To insure accurate positioning of the teeth in the denture in this respect, the present invention contemplates an instrument by which the distance between the patients lip and gum can be readily measured and said distance accurately indicated on the denture or the wax mold used in producing the final denture.

A further object is to provide an instrument of this character which is inexpensive and composed of a minimum number of parts, the instrument, as a whole, being very simple and easily manipulated.

More specifically, the invention contemplates an instrument of this nature, composed essentially of a bar having a sleeve slidable thereover with means for clamping the sleeve in any desired position longitudinally of said bar. One end of said sleeve projects beyond the bar and is adapted to be positioned against the gum of the patient while a pin or other projection on the bar is positioned against the patients lip, the distance between the pin and the gum engaging end of the sleeve denoting the distance between the gum and lip line of the patient. The opposite end of the bar is curved or of hook-like formation to engage in the gum recess of a denture and the spacing of this curved extremity and said sleeve is such as to correspond to the spacing of said pin and the gum engaging end of the sleeve so that when the lip line, so-called, of the patient is measured, the sleeve is simultaneously adjusted with respect to the curved extremity of the bar and by placing the curved extremity in the gum recess of the denture or denture mold, the lip line will be indicated on the mold by the position of said sleeve.

With these and other objects in View, the invention consists in certain details of construction and combinations and arrangements of parts, all as will hereinafter be more fully described and the novel features thereof particularly pointed out in the appended claims.

In the accompanying drawing illustrating the preferred embodiment of the invention Figure 1 illustrates the profile of a patient with the present instrument in place to measure the patients lip line;

Fig. 2 is a perspective View illustrating the use of the instrument for denoting the lip line on a denture or denture mold;

Fig. 3 is a vertical sectional view through the instrument and denture mold;

Fig. 4 is a sectional view on the line 4-4 of Fig. 3; and

Fig. 5 is a sectional View transversely of the instrument as indicated by the line 55 of Fig. 4.

In the preferred embodiment of the invention, the instrument comprises a rod or shank-like portion ill on which there is slidably mounted a sleeve H. Said sleeve is provided with a longitudinal slot l2 for a lateral projection on the rod, said projection consisting of a pin l3 threaded into bar I!) adjacent one end thereof and a thumb screw l4 having a tubular portion threaded on the pin by means of which sleeve l I may be clamped in any desired position longitudinally of bar Ill. The opposite end of bar 10 is offset or curved to form a hook-like portion [5 for purposes which will hereinafter appear. The length of sleeve H is such that the distance between the lateral projection on the rod, i. e., the exterior of the tubular portion of screw l4 and the adjacent end of said sleeve corresponds substantially to the distance between the end of the offset portion l5 of said bar and a predetermined point on said sleeve. For instance, in the present construction, the end of the sleeve adjacent hook-like portion I5 is formed with more or less of an annular knife edge It and the distance between said so-called knife edge and the extremity of hook l5, regardless of the position to which the sleeve may be adjusted on bar i 5, substantially corresponds to the distance between screw 14 and the other end of said sleeve. This is made clear in Fig. 3 of the drawing, where the distance between the several points is indicated by the dot and dash lines, the distance between the extremity of book portion I5 and knife edge I6 being indicated at a and the distance between screw l4 and the adjacent end of the sleeve being indicated at b, these two distances a, b, corresponding to each other.

In the use of the instrument, the end of the sleeve adjacent pin I3 is placed in the mouth of the patient, as indicated in Fig. 1. The end of the sleeve is positioned against the patients gum with the lateral projection formed by pin l3 and screw I l positioned against the patients lip. The sleeve is then clamped on bar by a screw nut l4. With the sleeve locked on the bar in this fashion, the distance between the end of the sleeve and the screw or pin will denote the distance from the patients gum to the patients lip line. This distance, as previously pointed out, will also correspond to the distance between knife edge 16 and the ofiset portion l of the instrument. Consequently, after the denture IT is made up, the hook-shaped extremity 15 of the instrument can be inserted or engaged in the gum recess of the denture mold and by imparting pivotal movement to the instrument with knife edge IS in engagement with the exterior surface of the mold (Fig. 2) a line l8 can be scored or marked on the mold with the knife, edge. This pivotal movement of the instrument takes place with the curved extremity l5 functioning as a pivot, and in view of the fact that the distance between the curved extremity and the knife edge l6 corresponds to the distance between the patients lip line and the patients gum, the line I8, indicated on the mold, will mark off the equivalent of the patients lip line with respect to the gum engaging recess of the mold. In other words, when the teeth are placed in the mold one by one, preparatory to making the ultimate denture, the lower extremities of the teeth will be positioned in registry with the line l8. As a result, when the final denture is made from the mold, the lower extremities of the teeth will register with the lip line of the patient.

While the present instrument is very simple in construction, it will be seen that it possesses the characteristic of absolute accuracy in determining the position of teeth in a denture relatively to the lip line of a patient. Only one adjustment is necessary for the instrument and, after that adjustment has been made, there is no possibility of error being committed in calculating, so to speak, the lip line on the denture mold and, consequently, the final denture itself.

What I claim is:

1. In an instrument for determining the location of frontal teeth in a denture relative to the lip line of a patient, a bar, a lateral projection on said bar, a member adjustable on said bar relatively to said projection and adapted to be positioned against the patients gum with said projection in engagement with the lip of the patient to measure the distance between the gum and lip line, and means on said bar engageable in the gum engaging recess of the denture, the location of said last-mentioned means relatively to a predetermined point on said adjustable member corresponding to the relative positioning of said projection and the gum engaging portion of said member.

2. In an instrument for determining the location of teeth in a denture relative to the lip line of a patient, a bar, means carried by said bar engageable against the patients lip, a slide on said bar movable relatively to said lip engaging means adapted to be positioned against the patients gum, and means on said bar engageable in the gum recess of the denture, the distance between a predetermined point on said slide and the last-mentioned means corresponding to the distance between said lip engaging means and the gum engaging portion of said slide.

3. In an instrument for determining the location of teeth in a denture relatively to the lip line of a patient, a bar, a lateral projection on said bar, a slotted sleeve on said bar movable relatively to said projection, one end of said sleeve being adapted to be positioned against the gum of the patient with said projection positioned against the patients lip, to denote the distance between the lip and gum, and means on said bar engageable in the gum recess of the denture, the distance between said means and the opposite end of said sleeve corresponding to the distance between said projection and the first-mentioned end of the sleeve.

4. In an instrument for determining the location of teeth in a denture relatively to the lip line of a patient, a bar having one end curved to engage in the gum recess of the denture, a lip engaging projection on said bar, and a sleeve slidable on said bar projecting beyond the opposite end of the bar and adapted to engage against the patients gum, the distance between said projection and the gum engaging portion of the sleeve substantially corresponding to the distance between a fixed point on said sleeve and the curved extremity of said bar.

5. In an instrument for determining the location of teeth in a denture relatively to the lip line of a patient, a bar having an offset end portion adapted to engage the bottom of the gum recess of a denture mold, a lateral projection on said bar adapted to be positioned against the patients lip, a sleeve slidable on said bar adapted to be positioned against the patients gum, and means on said sleeve for indicating the lip line of the patient on said mold the distance between said last-mentioned means and the recess-engaging portion of said ofiset end corresponding to the distance between the gum-engaging portion of the sleeve and said lateral projection.

LUCIAN G. COBLE. 

